Research On High Elastic Modified Asphalt Used In Overlay Of The Cement Concrete Pavement

Asphalt concrete surface that is paved over the old cement concrete panel can improve road performance effectively, extend its service life, and reduce the road reconstruction project cost. In this paper, the damage condition and structure performance of cement concrete pavement are assessed and the new and efficient asphalt; pavement overlay projects is presented, basing on the old cement; concrete pavement disease investigation of the real road reconstruction S103Wanyun road Wanzhou section, the road deflection test results as well as mechanical index test results of the concrete panel core samples.This paper focuses on high elastic modified asphalt performance and the mixture road performance. The results shows that, firstly, high elastic modified asphalt has the excellent performance in the high temperature or low temperature, and the PG classification of high elastic modified asphalt is PG88-26, according the asphalt performance standard in the plan named SHRP. The high elastic modified asphalt has excellent resistance to fatigue. When the temperature is19℃, the fatigue factor of high elastic modified asphalt is only2284kPa, which is far less than the specification require5000kPa. Secondly, high elastic modified asphalt mixture can prevent the occurrence of damage due to the over load vehicle, because high elastic modified asphalt mixture has high dynamic modulus at high temperature, and high elastic modified asphalt mixture has. stronger ability to resist deformation, rut and fatigue properties. High elastic modified asphalt mixture has small bending stiffness modulus and powerful anti-deformation ability, so high elastic modified asphalt mixture can prevent the bottom of the asphalt surface from cracking and developing effectively, and then reduce and defer reflective cracking on the asphalt surface. High elastic modified asphalt mixture can prevent asphalt pavement from water damage, because flooding residual stability degrees of high elastic modified asphalt mixture is95%, and the ratio of freeze-thaw splitting residual strength is94%. Thirdly, in order to effectively solve the problem the small-scale processing high elastic modified asphalt, such as segregation and unstable performance, the new technology, mixing general SBS modified asphalt and aggregate added SBS modifier, is proposed, through comparing with road performance high elastic modified asphalt mixture which is mixed by two different produce technology.This content of this paper can provide reference for high elastic modified asphalt used in the old road reconstruction project.